In manufacturing lenses, and particularly lenses for use with eye glasses, the use of plastic is often desirable due to its weight and durability. Normally in manufacturing plastic lenses, two molds in conjunction with a gasket are sealed in a spaced relationship to provide a mold cavity therebetween. This mold cavity ultimately forms the shape, curvature, thickness and configuration of the product lens. Resin material is dispensed into the mold cavity and cured to harden the lens with the exterior surfaces being configured to a particular patient's prescription.
The mold forms which actually constitute the mold have been in the past made of metal or glass which are ground or formed to the desired shape to create the prescription and made by the optometrist, ophthalmologist or optician. Utilizing molds made of metal or glass for this purpose is an expensive proposition for both the manufacturer and the user. Whether glass or metal is used it is initially cast and then ground to the desired configuration. A number of different configurations are required to ensure that the desired prescription can be made from these expensive mold forms. These types of molds have produced economic and manufacturing impediments to using certain casting processes in many facilities.
Sets of mold forms which will allow casting of a wide range of prescriptions are very expensive, costing in many instances more than $200 per mold. Progressive molds are even more expensive. Entire sets of molds can cost tens of thousands of dollars. Moreover, each time a new lens size or style is introduced an entire new set of molds must be purchased. As a result, keeping an inventory of conventional molds presents a significant component of overhead for an optical casting lab and has limited the success of in-office casting.
It would, therefore, be beneficial to provide a method for making molds for optical quality lenses, preferably spectacle lenses, which is both convenient and economical, such that a wide range of molds can be inexpensively produced. To date no such disposable lens mold is commercially available in the optical industry.